organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2,4-Bis(2-bromo­phen­yl)-3-aza­bi­cyclo­[3.3.1]nonan-9-one

aDivision of Image Science and Information Engineering, Pukyong National University, Busan 608 739, Republic of Korea, and bDepartment of Chemistry, IIT Madras, Chennai, Tamilnadu, India
*Correspondence e-mail: ytjeong@pknu.ac.kr

(Received 10 November 2008; accepted 12 November 2008; online 20 November 2008)

In the mol­ecular structure of the title compound, C20H19Br2NO, the fused six-membered heterocyclic and cyclo­hexane rings adopt a twin-chair conformation with equatorial orientations of all the substituents. Both the ortho-bromo substituents of the benzene rings are oriented towards the carbonyl group; the dihedral angle between the ring planes is 29.13 (3)°. In the crystal structure, the N—H group does not participate in any hydrogen bonds.

Related literature

For 3-aza­bicyclo­nonan-9-ones and their significance as bio-active mol­ecules, see: Barker et al. (2005[Barker, D., Lin, D. H. S., Carland, J. E., Chu, C. P. Y., Chebib, M., Brimble, M. A., Savage, G. P. & McLeod, M. D. (2005). Bioorg. Med. Chem. 13, 4565-4575.]); Jeyaraman & Avila (1981[Jeyaraman, R. & Avila, S. (1981). Chem. Rev. 81, 149-174.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Web & Becker (1967[Web, N. C. & Becker, M. R. (1967). J. Chem. Soc. B, 1317-1321.]). For a similiar structure see; Parthiban et al. (2008[Parthiban, P., Ramkumar, V., Kim, M. S., Lim, K. T. & Jeong, Y. T. (2008). Acta Cryst. E64, o1586.]).

[Scheme 1]

Experimental

Crystal data
  • C20H19Br2NO

  • Mr = 449.18

  • Triclinic, [P \overline 1]

  • a = 7.8389 (3) Å

  • b = 10.5770 (3) Å

  • c = 11.0274 (3) Å

  • α = 101.099 (2)°

  • β = 93.725 (2)°

  • γ = 97.399 (1)°

  • V = 885.94 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 4.58 mm−1

  • T = 298 (2) K

  • 0.45 × 0.38 × 0.35 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1999[Bruker (1999). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.232, Tmax = 0.297 (expected range = 0.157–0.201)

  • 10959 measured reflections

  • 4098 independent reflections

  • 3266 reflections with I > 2σ(I)

  • Rint = 0.017

Refinement
  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.060

  • S = 1.00

  • 4098 reflections

  • 221 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.58 e Å−3

  • Δρmin = −0.56 e Å−3

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). APEX2 and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

3-Azabicyclononan-9-ones are important class of compounds due to their significance as bio-active molecules (Jeyaraman & Avila, 1981; Barker et al., 2005).

The title compound, (I), exists in a chair–chair conformation with equatorial orientations of the ortho bromo-phenyl groups on each side of the secondary amino group with the torsion angles of C8—C2—C1—C9 and C8—C6—C7—C15 being 177.88 (4) and 179.42 (6)°, respectively. In both aryl groups, the bromo substituents point towards the carbonyl group and the dihedral angle between the ring planes is 29.13 (3)°. The piperidine ring adopts near ideal chair conformation with the deviation of ring atoms N1 and C8 from the C1/C2/C6/C7 plane by -0.635 (3)and 0.705 (3)Å, respectively, QT = 0.599 (2)Å, q(2)=0.047 (2)Å, q(3)=0.597 (2)Å, θ = 4.71 (19)° Cremer & Pople, 1975; Web & Becker, 1967), whereas the cyclohexane ring atoms C4 and C8 deviate from the C2/C3/C5/C6 plane by -0.539 (4) and 0.725 (3)Å, respectively, QT = 0.565 (2)Å, q(2)=0.141 (2)Å, q(3)=0.548 (2)Å, θ = 14.4 (2)°, indicating a deviation from the ideal chair conformation of the cyclohexane part in the title compound. The crystal structure is stabilized by the intermolecular van der Waals interactions.

Related literature top

For 3-azabicyclononan-9-ones and their significance as bio-active molecules, see: Barker et al. (2005); Jeyaraman & Avila (1981). For puckering parameters, see: Cremer & Pople (1975); Web & Becker (1967). For a similiar structure see; Parthiban et al. (2008).

Experimental top

A mixture of cyclohexanone (0.05 mol) and ortho bromobenzaldehyde (0.1 mol) was added to a warm solution of ammonium acetate (0.075 mol) in 50 ml of absolute ethanol. The mixture was gently warmed on a hot plate until a yellow colour was formed and then cooled to room temperature. Then, 50 ml of ether was added and allowed to stir over night at room temperature. At the end, the crude azabicyclic ketone was separated by filtration and washed with 1:5 v/v ethanol–ether mixture till the solid became colourless. Recrystallization of the compound from acetone gave colourless blocks of (I).

Refinement top

The nitrogen-bound H atom was located in a difference map and refined isotropically. The other hydrogen atoms were fixed geometrically (C—H = 0.93–0.98Å) and refined as riding with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with non-hydrogen atoms represented as 30% probability ellipsoids.
2,4-Bis(2-bromophenyl)-3-azabicyclo[3.3.1]nonan-9-one top
Crystal data top
C20H19Br2NOZ = 2
Mr = 449.18F(000) = 448
Triclinic, P1Dx = 1.684 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.8389 (3) ÅCell parameters from 5642 reflections
b = 10.5770 (3) Åθ = 2.5–28.2°
c = 11.0274 (3) ŵ = 4.58 mm1
α = 101.099 (2)°T = 298 K
β = 93.725 (2)°Block, colourless
γ = 97.399 (1)°0.45 × 0.38 × 0.35 mm
V = 885.94 (5) Å3
Data collection top
Bruker APEXII CCD
diffractometer
4098 independent reflections
Radiation source: fine-focus sealed tube3266 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.017
ω scansθmax = 28.3°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 1999)
h = 1010
Tmin = 0.232, Tmax = 0.297k = 1313
10959 measured reflectionsl = 1414
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.027Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.060H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0207P)2 + 0.5638P]
where P = (Fo2 + 2Fc2)/3
4098 reflections(Δ/σ)max = 0.002
221 parametersΔρmax = 0.58 e Å3
0 restraintsΔρmin = 0.56 e Å3
Crystal data top
C20H19Br2NOγ = 97.399 (1)°
Mr = 449.18V = 885.94 (5) Å3
Triclinic, P1Z = 2
a = 7.8389 (3) ÅMo Kα radiation
b = 10.5770 (3) ŵ = 4.58 mm1
c = 11.0274 (3) ÅT = 298 K
α = 101.099 (2)°0.45 × 0.38 × 0.35 mm
β = 93.725 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
4098 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1999)
3266 reflections with I > 2σ(I)
Tmin = 0.232, Tmax = 0.297Rint = 0.017
10959 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0270 restraints
wR(F2) = 0.060H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.58 e Å3
4098 reflectionsΔρmin = 0.56 e Å3
221 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes)

are estimated using the full covariance matrix. The cell e.s.d.'s are taken

into account individually in the estimation of e.s.d.'s in distances, angles

and torsion angles; correlations between e.s.d.'s in cell parameters are only

used when they are defined by crystal symmetry. An approximate (isotropic)

treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and

goodness of fit S are based on F2, conventional R-factors R are based

on F, with F set to zero for negative F2. The threshold expression of

F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is

not relevant to the choice of reflections for refinement. R-factors based

on F2 are statistically about twice as large as those based on F, and R-

factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.00438 (3)0.47719 (2)0.77681 (2)0.05065 (8)
Br20.16949 (3)1.23193 (3)1.01448 (2)0.06070 (9)
C10.2124 (2)0.74756 (18)0.75331 (18)0.0301 (4)
H10.14370.73700.82280.036*
C20.0889 (2)0.76537 (19)0.64395 (19)0.0344 (4)
H20.00490.69180.62540.041*
C30.1735 (3)0.7773 (2)0.5238 (2)0.0428 (5)
H3A0.22940.70110.49800.051*
H3B0.08390.77780.45910.051*
C40.3064 (3)0.8987 (2)0.5360 (2)0.0432 (5)
H4A0.41190.88650.58060.052*
H4B0.33330.91020.45390.052*
C50.2434 (3)1.0214 (2)0.60396 (19)0.0392 (5)
H5A0.16471.05000.54680.047*
H5B0.34181.08950.62800.047*
C60.1515 (2)1.00528 (19)0.72040 (18)0.0331 (4)
H60.09671.08280.74790.040*
C70.2692 (2)0.98341 (18)0.83118 (17)0.0294 (4)
H70.19870.97470.90010.035*
C80.0132 (2)0.8886 (2)0.68529 (18)0.0342 (4)
C90.3014 (2)0.62834 (18)0.72007 (17)0.0304 (4)
C100.4692 (3)0.6383 (2)0.6847 (2)0.0389 (5)
H100.52650.71940.67960.047*
C110.5525 (3)0.5302 (2)0.6570 (2)0.0495 (6)
H110.66410.53920.63280.059*
C120.4711 (3)0.4095 (2)0.6651 (2)0.0556 (6)
H120.52800.33710.64720.067*
C130.3055 (3)0.3958 (2)0.6995 (2)0.0482 (6)
H130.24960.31420.70470.058*
C140.2228 (3)0.50413 (19)0.72632 (19)0.0350 (4)
C150.4125 (2)1.09742 (18)0.87430 (17)0.0290 (4)
C160.3860 (3)1.21258 (19)0.95107 (18)0.0337 (4)
C170.5159 (3)1.3181 (2)0.9863 (2)0.0436 (5)
H170.49461.39381.03800.052*
C180.6757 (3)1.3104 (2)0.9446 (2)0.0499 (6)
H180.76291.38120.96700.060*
C190.7071 (3)1.1976 (2)0.8696 (2)0.0482 (6)
H190.81611.19200.84210.058*
C200.5772 (3)1.0923 (2)0.8347 (2)0.0381 (5)
H200.60031.01660.78390.046*
N10.3422 (2)0.86343 (15)0.79409 (16)0.0304 (4)
O10.13950 (19)0.89419 (17)0.68681 (16)0.0521 (4)
H1A0.407 (3)0.851 (2)0.850 (2)0.040 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.04366 (13)0.03775 (13)0.06740 (17)0.00469 (9)0.01281 (11)0.00737 (11)
Br20.05389 (15)0.06429 (18)0.05949 (17)0.02181 (12)0.01497 (12)0.01039 (13)
C10.0296 (9)0.0256 (10)0.0349 (10)0.0042 (7)0.0038 (8)0.0056 (8)
C20.0286 (9)0.0300 (10)0.0415 (11)0.0019 (8)0.0038 (8)0.0035 (9)
C30.0511 (13)0.0398 (12)0.0351 (11)0.0125 (10)0.0022 (10)0.0001 (9)
C40.0505 (13)0.0492 (13)0.0325 (11)0.0104 (10)0.0097 (9)0.0107 (10)
C50.0441 (11)0.0369 (12)0.0386 (12)0.0063 (9)0.0008 (9)0.0138 (9)
C60.0326 (10)0.0299 (10)0.0371 (11)0.0102 (8)0.0012 (8)0.0046 (8)
C70.0300 (9)0.0276 (10)0.0302 (10)0.0044 (7)0.0033 (7)0.0049 (8)
C80.0310 (9)0.0405 (12)0.0327 (11)0.0088 (8)0.0003 (8)0.0100 (9)
C90.0335 (9)0.0278 (10)0.0295 (10)0.0060 (8)0.0003 (8)0.0046 (8)
C100.0357 (10)0.0380 (12)0.0448 (12)0.0081 (9)0.0059 (9)0.0104 (9)
C110.0417 (12)0.0553 (15)0.0575 (15)0.0220 (11)0.0123 (11)0.0135 (12)
C120.0657 (16)0.0446 (14)0.0637 (16)0.0311 (12)0.0140 (13)0.0109 (12)
C130.0608 (15)0.0297 (12)0.0551 (14)0.0101 (10)0.0065 (11)0.0083 (10)
C140.0371 (10)0.0304 (10)0.0362 (11)0.0041 (8)0.0025 (8)0.0038 (8)
C150.0314 (9)0.0280 (10)0.0284 (10)0.0053 (8)0.0005 (7)0.0079 (8)
C160.0403 (10)0.0322 (11)0.0297 (10)0.0100 (8)0.0010 (8)0.0062 (8)
C170.0646 (15)0.0278 (11)0.0353 (12)0.0034 (10)0.0054 (10)0.0047 (9)
C180.0547 (14)0.0427 (13)0.0455 (13)0.0154 (11)0.0072 (11)0.0108 (11)
C190.0346 (11)0.0573 (15)0.0500 (14)0.0043 (10)0.0028 (10)0.0117 (12)
C200.0337 (10)0.0375 (11)0.0411 (12)0.0048 (9)0.0047 (9)0.0029 (9)
N10.0292 (8)0.0249 (8)0.0362 (9)0.0055 (6)0.0050 (7)0.0053 (7)
O10.0292 (7)0.0588 (11)0.0693 (11)0.0119 (7)0.0028 (7)0.0120 (9)
Geometric parameters (Å, º) top
Br1—C141.903 (2)C7—H70.9800
Br2—C161.897 (2)C8—O11.207 (2)
C1—N11.465 (2)C9—C101.393 (3)
C1—C91.515 (3)C9—C141.394 (3)
C1—C21.552 (3)C10—C111.382 (3)
C1—H10.9800C10—H100.9300
C2—C81.505 (3)C11—C121.373 (4)
C2—C31.539 (3)C11—H110.9300
C2—H20.9800C12—C131.373 (3)
C3—C41.524 (3)C12—H120.9300
C3—H3A0.9700C13—C141.381 (3)
C3—H3B0.9700C13—H130.9300
C4—C51.525 (3)C15—C201.393 (3)
C4—H4A0.9700C15—C161.391 (3)
C4—H4B0.9700C16—C171.387 (3)
C5—C61.539 (3)C17—C181.369 (3)
C5—H5A0.9700C17—H170.9300
C5—H5B0.9700C18—C191.375 (4)
C6—C81.506 (3)C18—H180.9300
C6—C71.554 (3)C19—C201.385 (3)
C6—H60.9800C19—H190.9300
C7—N11.457 (2)C20—H200.9300
C7—C151.518 (2)N1—H1A0.81 (2)
N1—C1—C9109.63 (15)O1—C8—C2124.48 (19)
N1—C1—C2110.38 (16)O1—C8—C6123.98 (19)
C9—C1—C2112.32 (16)C2—C8—C6111.51 (16)
N1—C1—H1108.1C10—C9—C14116.51 (18)
C9—C1—H1108.1C10—C9—C1121.26 (17)
C2—C1—H1108.1C14—C9—C1122.21 (17)
C8—C2—C3107.21 (17)C11—C10—C9121.5 (2)
C8—C2—C1107.83 (16)C11—C10—H10119.3
C3—C2—C1115.42 (16)C9—C10—H10119.3
C8—C2—H2108.7C12—C11—C10120.3 (2)
C3—C2—H2108.7C12—C11—H11119.9
C1—C2—H2108.7C10—C11—H11119.9
C4—C3—C2114.03 (17)C13—C12—C11119.9 (2)
C4—C3—H3A108.7C13—C12—H12120.1
C2—C3—H3A108.7C11—C12—H12120.1
C4—C3—H3B108.7C12—C13—C14119.5 (2)
C2—C3—H3B108.7C12—C13—H13120.3
H3A—C3—H3B107.6C14—C13—H13120.3
C5—C4—C3112.67 (18)C13—C14—C9122.3 (2)
C5—C4—H4A109.1C13—C14—Br1116.76 (16)
C3—C4—H4A109.1C9—C14—Br1120.89 (15)
C5—C4—H4B109.1C20—C15—C16116.80 (18)
C3—C4—H4B109.1C20—C15—C7120.81 (17)
H4A—C4—H4B107.8C16—C15—C7122.36 (17)
C4—C5—C6114.82 (17)C17—C16—C15122.0 (2)
C4—C5—H5A108.6C17—C16—Br2116.64 (16)
C6—C5—H5A108.6C15—C16—Br2121.32 (15)
C4—C5—H5B108.6C18—C17—C16119.7 (2)
C6—C5—H5B108.6C18—C17—H17120.2
H5A—C5—H5B107.5C16—C17—H17120.2
C8—C6—C5108.13 (16)C17—C18—C19119.9 (2)
C8—C6—C7107.18 (16)C17—C18—H18120.0
C5—C6—C7115.25 (16)C19—C18—H18120.0
C8—C6—H6108.7C18—C19—C20120.3 (2)
C5—C6—H6108.7C18—C19—H19119.9
C7—C6—H6108.7C20—C19—H19119.9
N1—C7—C15110.21 (15)C19—C20—C15121.3 (2)
N1—C7—C6109.31 (15)C19—C20—H20119.3
C15—C7—C6111.09 (15)C15—C20—H20119.3
N1—C7—H7108.7C7—N1—C1113.89 (15)
C15—C7—H7108.7C7—N1—H1A111.0 (16)
C6—C7—H7108.7C1—N1—H1A108.6 (16)
N1—C1—C2—C855.2 (2)C9—C10—C11—C120.6 (4)
C9—C1—C2—C8177.89 (16)C10—C11—C12—C130.7 (4)
N1—C1—C2—C364.6 (2)C11—C12—C13—C140.3 (4)
C9—C1—C2—C358.1 (2)C12—C13—C14—C90.2 (3)
C8—C2—C3—C455.1 (2)C12—C13—C14—Br1178.65 (19)
C1—C2—C3—C465.0 (2)C10—C9—C14—C130.2 (3)
C2—C3—C4—C545.4 (3)C1—C9—C14—C13178.10 (19)
C3—C4—C5—C643.4 (3)C10—C9—C14—Br1178.65 (15)
C4—C5—C6—C851.3 (2)C1—C9—C14—Br10.3 (3)
C4—C5—C6—C768.6 (2)N1—C7—C15—C2023.6 (2)
C8—C6—C7—N158.74 (19)C6—C7—C15—C2097.7 (2)
C5—C6—C7—N161.6 (2)N1—C7—C15—C16158.48 (18)
C8—C6—C7—C15179.43 (15)C6—C7—C15—C1680.2 (2)
C5—C6—C7—C1560.2 (2)C20—C15—C16—C170.5 (3)
C3—C2—C8—O1113.0 (2)C7—C15—C16—C17177.53 (18)
C1—C2—C8—O1122.1 (2)C20—C15—C16—Br2178.76 (15)
C3—C2—C8—C664.9 (2)C7—C15—C16—Br23.2 (3)
C1—C2—C8—C659.9 (2)C15—C16—C17—C180.3 (3)
C5—C6—C8—O1114.9 (2)Br2—C16—C17—C18179.52 (17)
C7—C6—C8—O1120.3 (2)C16—C17—C18—C190.9 (3)
C5—C6—C8—C263.1 (2)C17—C18—C19—C200.8 (4)
C7—C6—C8—C261.7 (2)C18—C19—C20—C150.0 (3)
N1—C1—C9—C1024.4 (3)C16—C15—C20—C190.6 (3)
C2—C1—C9—C1098.7 (2)C7—C15—C20—C19177.4 (2)
N1—C1—C9—C14153.82 (18)C15—C7—N1—C1178.86 (15)
C2—C1—C9—C1483.1 (2)C6—C7—N1—C158.8 (2)
C14—C9—C10—C110.2 (3)C9—C1—N1—C7178.59 (16)
C1—C9—C10—C11178.5 (2)C2—C1—N1—C757.2 (2)

Experimental details

Crystal data
Chemical formulaC20H19Br2NO
Mr449.18
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)7.8389 (3), 10.5770 (3), 11.0274 (3)
α, β, γ (°)101.099 (2), 93.725 (2), 97.399 (1)
V3)885.94 (5)
Z2
Radiation typeMo Kα
µ (mm1)4.58
Crystal size (mm)0.45 × 0.38 × 0.35
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1999)
Tmin, Tmax0.232, 0.297
No. of measured, independent and
observed [I > 2σ(I)] reflections
10959, 4098, 3266
Rint0.017
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.060, 1.00
No. of reflections4098
No. of parameters221
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.58, 0.56

Computer programs: APEX2 (Bruker, 2004), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

 

Acknowledgements

The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection.

References

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